From the Rolls-Royce experimental archive: a quarter of a million communications from Rolls-Royce, 1906 to 1960's. Documents from the Sir Henry Royce Memorial Foundation (SHRMF).
Proposal for a Bentley camshaft timing for use with silent tappets.
| Identifier | ExFiles\Box 88\4\ scan0126 | |
| Date | 4th December 1934 | |
| 4254 Hs{Lord Ernest Hives - Chair}/Smth.8/KW.4.12.34. Bentley - Camshaft for use with Silent Tappets. The slow running of the Bentley engine will be very bad if silent tappets are used in connection with the present camshaft. The overlap cannot be reduced with the present forms or the I.C. & E.O points will be too high. The inlet form developed for SpectreCodename for Phantom III to LeC.3855 has 5° less duration than the Bentley form, without sacrificing much valve lift. We therefore suggest that this form be adapted to Bentley, using the following timing - TDC Ex 230° IN 230° 50° 50° Timing with .020 clearance 115° between the cams. Hs.{Lord Ernest Hives - Chair}1636 gives the cam form required. Hs{Lord Ernest Hives - Chair}/F.Ll.Smith. | ||